code: def test_pandas_multivariate_rangeindex():
      # Impulse responses have RangeIndex
      endog = pd.DataFrame(np.zeros((1, 2)))
      mod = varmax.VARMAX(endog, trend="n")
      res = mod.filter([0.5, 0.0, 0.0, 0.2, 1.0, 0.0, 1.0])
  
      actual = res.impulse_responses(2)
      desired = pd.DataFrame([[1.0, 0.5, 0.25], [0.0, 0.0, 0.0]]).T
      assert_allclose(actual, desired)
      assert_(actual.index.equals(desired.index))
  
imports: from statsmodels.compat.pandas import MONTH_END
  import warnings
  import numpy
  from numpy.testing import assert_, assert_allclose
  import pandas
  import pytest
  from scipy.stats import ortho_group
  from statsmodels.tools.sm_exceptions import EstimationWarning
  from statsmodels.tsa.statespace import dynamic_factor, mlemodel, sarimax, structural, varmax
  from statsmodels.tsa.vector_ar.tests.test_var import get_macrodata
label_desc: Use image node_id 13 for calling a global function with example usage: test_pandas_multivariate_rangeindex() without return types